How to display items in a centered Flow-like way?

Hi, I was wondering if there was a way to display child items in the way the Flow item does (side by side as long as there is enough room and then on the following row/column depending on the orientation/disposition)… but in centered way. That is to say, with an horizontal disposition, each “row” of items to be horizontally centered in the Flow item. And of course, with a vertical disposition, each “column” of items to be vertically centered in the Flow item. For example, within a Flow item with spacing property of 0 and containing 3 items each of width half the flow width, to have the 3rd item centered on its row; but to have it look like a grid when a 4th similar item is added. I cannot anchor statically the contained items since the container size as much as the quantity of contained items may may change. Any idea on how I can achieve such a thing? I am currently developing on Qt5.1 beta, so using a Layout item from QtQuickControls.Layout module is totally acceptable. Thanks in advance.